Electrical incandescent lamp.



W. NERNST.

ELECTRICAL INGANDESOENT LAMP.

APPLICATION FILED corzo, 1897.

906,550. Patented Dec. 15,1908.

2 SHEETSSHEBT 1.

K P G W. NERNST.

ELECTRICAL INOANDESOEN T LAMP. APPLICATION FILED oomo, 1897.

906,550. Patented Dec. 15, 1908.

2 BHBETSSHEET 2.

WITNESSES" //VVENT0R K V 038 A fioRNEv-gw UNITED STATES PATENT OFFICE.

WALTHER NERNST, OF GOTTINGEN, GERMANY, ASSIGNOR, BY MESNE ASSIGNMENTS, TO

NERNST LAMP COMPANY, OF PITTSBURG, PENNSYLVANIA, A CORPORATION OF PENN- SYLVAN IA.

' descent lamps the incandescent body of which is not made of a material being a conductor of electricity at the ordinary temperature, but only becoming a conductor when it is heated to a high temperature, such as magnesia, zirconia, lime and other oxids of.

metals.

The invention consists in an a paratus for establishing in the incandescent ody of such lamps the high temperature necessary for transforming it into a conductor of elec tricity.

Of the accompanying drawings Figure 1 is a diagrammatic view of a lamp constructed according to my invention partly in section, Fig. 2 is a similar view showing a modification of the lamp given in Fig. 1, Fig. 3 is a diagrammatic vlew of a second modification, and Fig. 4 is a diagrammatic view showing modifications.

The letters of reference designate the same parts in all the figures.

Gis the incandescent body corresponding to the carbon filament in the ordinary glowlamp, but made in this case of an 0X1d of a foetal preferably of magnesia, zirconia or ime.

K K and K K (Fig. 3) are binding posts supposed to be connected with the poles of some source of electricity such as E, (Fig. 3) and conducting the current generated to the incandescent body G.

b TIhe circuit leading to G is designated P is a coiled or s iral sha ed wire of some heatproof electrica ly con uctive material preferably platina.

M is a sleeve or mantle of heatproof and nonconductive material such as for instance porcelain.

The resistance P is sup osed to be inserted in a second circuit II fed y a separate source of electricity E (Fig. 3) or else derived from the main circuit I, as in Fig. 4.

S (Fig. 3) is a coil or solenoid surrounding Specification of Letters Patent.

Application filed October 20, 1897.

ELECTRICAL INCANDESOENT LAMP.

Patented Dec. 15, 1908.

Serial No. 665,771.

the lower end of an iron core at n, which is suspended from a spring F hung in a fixed part II of the frame of the instrument.

G, Fig. 3, is suspended from a n.

K, and K are electrically connected by pliable conductors such as copper ribbons L,, L,,, or the like to K and K The operation of my lamp is as follows. Both circuits I and II are closed. In the circuit I no current at first can be generated because the body G which is inserted in this circuit acts as an insulator until heated to a high temperature. In circuit II however a current is generated and heats the resistance I The latter imparts its heat to the sleeve or mantle M and thence by radiation to G. As soon as G thus becomesincandescent, it also becomes a conductor and consequently a current is set up in I which henceforth keeps G glowing. Circuit II can now be interrupted either by hand or by any known automatic means.

In the construction shown in Fig. 1 it is assumed that the sleeve M is made of some transparent material such as for instance glass. In that case although the body G remains covered by the sleeve M, it is not prevented from emitting light.

In the modification shown in Fig. 2 the mantle M is constructed in the shape of a concave mirror, so that it will concentrate the heat rays it emits on the body G which is placed in its focus.

The device shown in Fig. 3 acts in the followin manner. As soon as the temperature of G has been sufficiently raised to make it conduct the current generated in E,, that current passes through K L K,, G, K,, L,,K ,S and back to E The coilS therefore becomes excited and sucks in the iron core n 'n thereby at the same time lowering the incandescent body G and withdrawing it from the interior of the heating device P M. Evidently the device shown in Fig. 3 could also be so modified that the incandescent body G is fixed and the heating device P M is withdrawn from it automatically as soon as the current in circuit I is set up. This-is shown in Fig. 4, the device P M being supported from the core a so as to move with it when the core is raised by the combined action of spring F -and the coil S and the core drops on the cessation of curin its elevated position.

rent in coil S, spring F in this case being of insufficient strength to alone support core at In this figure circuit II is a shunt of circuit I, and includes means for automatically making and breaking the shunt, that is clrcuit II. a is a vulcanized fiber or other insulating plate supported on bracket 1) or otherwise. 0 is a contact plate fastened on a and connected by a wire W to the upper end of the spiral or coil P. I11 and L are two pliable conductors for instance copper ribbons the one I being connected to the lower end of the heating coil P the other L being connected to a contact pin (.3 fastened in, but insulated from, the iron core it. Each circuit I, II is provided with a switch SW SW, whereby they can be controlled manually when desired. It will be readily seen, that when the switch SW is closed, a current is set 11 in circuit II, assing through II, L,, P, 0, L and 8%,. body G is heated and as soon as it becomes conductive, a current will be set up in I, which at the same time excites the solenoid S, sucks in the core n and thereby disengages the contact 0 and automatically interrupts the circuit II.

Having now particularly described and ascertained the nature of mysaid invention Thereby the incandescent and in what manner the same is to be performed, I declare that what I claim is:

1. A combined support and heating conductor for use with electric lamps, comprising a heat-proof non-conducting material, a heating conductor arranged upon the inner surface thereof, a coil or solenoid and its armature, one or the other of which is attached to said su port, and means for moving the support y the action of a current traversing the solenoid, substantially as described.

2. The combination of a heating conductor, a support therefor of non-conducting material, and an electro-magnetic device for producing an axial movement of the heating device and its support when current traverses the electro-ma netic device.

v 3. The combination 0 a source of electric current, an electric heating conductor, a concave support carrying the heatin conductor upon its inner surface, and e ectromagnetic means for giving an axial movement to the support.

Si ned at Berlln, Germany, this 7th day of OctoIaer 1897.

WALTHER N ERNST. Witnesses:

LUDWIG KoNre, HENRY HASPER. 

